62 On Practical Geodesy. 



log 2 == 0-3010300 





log e^ = 3-8315592 





sin I (L" + V) = 1-8994540 





sin ^ (L" — r) = 3-9389661 





5-9710093 . 



. . . . 5-9710093 



cosL" = 1-7795064 



sinL" = 1-9023240 



5-7505157 



5-8733333 



antilog = 0000056300 



1-9970186 



l^^ = 0-993214854 



.-.• sin 8, = 5-8763147 



0-993158554 



.-. S, = 0°, 00', 15"-5146 



its log = 1-9970186 





Then to find V, and l^^, we have — 



I" = L" + 8,; I, = 90° — I" 



.\ By first value of h„ we find I,, = 37°,, 00',, 00"-0019 

 „ second „ „ , ^,, = 37°,, 00',, 00"-0004 



To find A^^, we have — 



A„ — D„ = sin D„ tan J z, ' 8„ 

 sin D„ = I-8456994 .*. A,,— D„ = 0°„ 00',, 00"-13336 

 tan 1 0^ = 2-0886210 but D,,=: 44°„ 30',, 17"-5430 



log 8„ = 1-1 907207 ... A„ = 44°,, 30',, 17"-6764 



/. log(A,,— DJ = r-1250411 



l^° In the "Account of the Principal Triangulation of 

 Great Britain and Ireland" (see pages 247, 249, 676, of that 

 work) there is given what is considered the most accurate 

 method of solving this problem. The values of z^, <d, D^^, are 

 there found as in the present paper, but the azimuth A^^ and 

 latitude l^^ are determined otherwise : thus — 



To find A^, the erroneous formula 96 is used, which gives 

 ^ = A^, — D^, = 0''-1315 instead of 0^'-1334. 



Then to find l^^ the following formula is given — 

 ] —I = ^ . sin \ (A, — A„ + ^) 



" p' sin 1" sin i (A, + A„ + Q 



. j 1 4- ^' . cos^ i (A, — A,,) sin2 1 l 

 in which p is the radius of curvature for the meridian for 



